Abstract: In a process according to the present invention pre-reduced lateritic ores containing iron and nickel are leached with an aqueous sulphuric acid leach liquor containing or into which is introduced in the presence of the ore a peroxidant selected from hydrogen peroxide and peroxymonosulphuric acid. By so doing, the liquor is obtained with a lower concentration of iron than if the peroxidant had not been employed.In preferred embodiments the leaching is carried out at from 40.degree. to 70.degree. C. for a period of 1 to 5 hours; when hydrogen peroxide is used, it is preferably introduced continuously or progressively throughout the reaction period and when peroxymonosulphuric acid is used it is preferably introduced initially. The acidity of the liquor can be reduced at the end of the reaction to pH3 to 4 to further lower the content of iron in solution.

Abstract: Metal values, such as iron, may be stripped from an organic liquid medium loaded with metal ions by a process which comprises contacting the organic medium with an aqueous phase at a contact temperature which is sufficiently high to cause the metal values to precipitate as metal oxide, hydroxide or hydrate (or a mixture thereof) in the presence of the organic medium.